Is it possible to set up a local yum repository for add-on software?  Do 
you have recipes for doing this that I could read?

I'm putting a cluster of machines together.  I have to install additional
software.  At present, I do this via a common NFS mount which is fine.  The
amount of work required to keep this up-to-date would be the same as keeping
a yum repo up-todate.  However, this does not work so well for add-ons that
are sharable libraries.  Here it seems more appropriate to install the
library rpm and have yum handle any updates.

So, the question is: Is it possible to set up a partial yum repo?  I
have in mind something along the lines of the sl-contrib repo.  I'd fill the
repo with updated rpms and let yum do the work.

Thanks!  Ken